AlgebraMediumLeast perimeter under a length condition
Algebra practice question
A rectangle has a width of 4 centimetres, and its length must be at least 3 times its width. What is the least possible perimeter of the rectangle, in centimetres?
Answer: 32
The least length is 12, giving a perimeter of 2(12 + 4) = 32.
Common wrong answers
- If you answered 16
- 16 is 12 + 4, half the perimeter.
- If you answered 24
- 24 comes from a length of 8 (twice the width).
- If you answered 48
- 48 is the area with the least length (12 × 4).
More Algebra questions
- Medium
A system: 2x + y = 11 and x − y = 1. What is the value of x + y? - Medium
Which of the following describes all solutions to 4x − 9 ≤ 2x + 5? - Medium
A phone's battery percentage is modeled by P = 100 − 8t, where t is the number of hours since it was unplugged… - Medium
If y = 2x − 1 and 3x + y = 14, what is the value of x? - Medium
If |2x − 3| = 7, what is the sum of all possible values of x? - Medium
Line k has equation y = (2/3)x + 1. Which equation represents a line perpendicular to line k?
Not affiliated with the College Board. SAT is a trademark of the College Board.